Conservation

Hihi conservation is currently overseen by the New Zealand Department of Conservation with active management moving more toward independent conservation organizations (see links below) and with an overseeing body (Hihi Recovery Group) with representatives from government, iwi, independent conservation groups and scientists.

Conservation management of the sole remnant population (Te Hauturu-o-Toi) has been minimal apart from maintaining the islands pest free status (cats removed in 1980 and kiore rats removed in 2004). Some research has been done to monitor the population’s size and demography although there is substantial uncertainty in how many birds are on the island (current estimates range from 1000-3000 birds). Instead, management has focused on establishing additional populations of hihi at other sites by translocation of wild caught hihi from Te Hauturu-o-Toi and more recently of juveniles and adults from Tiritiri Matangi.

Early attempts to establish hihi on additional islands were done entirely from a species-recovery perspective. Habitat quality was carefully considered, and islands were chosen based on their diversity and abundance of nectar – and fruit-producing species. Based on these considerations, a total of 7 translocations were made to Taranga (Hen) (1980 & 1981), Cuvier (1982 & 1985) and Kāpiti (1983, 1985 & 1990) islands. These reintroductions failed to establish populations. Although there was little monitoring on Taranga and Cuvier islands, the available information suggested that hihi bred well, at least initially, but nevertheless declined to extinction. Following these initial failures an additional two translocations were made to Kāpiti (1991 & 1992). More intense monitoring of these releases led to the hypothesis that an insufficient year-round supply of nectar and food was responsible. The continuing management of the Kāpiti Island population, primarily through maintaining the islands pest free status and providing supplementary food, has resulted in the successful establishment of a hihi population. In 2002 & 2010 additional releases of hihi were made.

Following the establishment of a population on Kāpiti, hihi were then released onto Mokoia Island (1994) and Tiritiri Matangi Island (1995, 1996 & 2010). Neither island was deemed to have a high probability of establishing populations of hihi without support in the form of supplementary food and nest boxes. However, the programs were useful for determining what management was necessary to maintain a viable hihi population and what level of restoration was required to support a self-sustaining population in the long term. Both populations have been intensively monitored. The Mokoia population was predicted to quickly decline to extinction if management (supplementary feeding and nest mite control) were stopped and even with such management there was uncertainty in continued viability. Therefore, all remaining hihi (10) were caught and moved from Mokoia to Kāpiti in 2002. In contrast, with continued supplementary feeding and nest management on Tiritiri Matangi, the population is doing well. The hihi translocation to Tiritiri Matangi was part of a restoration plan that included planting a wide variety of nectar – and fruit-producing species in the decade prior to hihi arrival. As these plantings mature, we are hopeful that supplementary feeding can be discontinued and allow this population to persist without need of supplementary feeding or nest boxes.

The productivity of hihi on Tiritiri Matangi has been so great that Tiritiri Matangi birds have been the source for translocations to six sites on Te Ika-a-Māui (North Island). Transfers to Zealandia ecosanctuary (2005), the Ark in the Park project of the Waitakere Ranges (2007 & 2008)

Sanctuary Mountain Maungatautari (2009, 2010 & 2011), Bushy Park Tarapuruhi (2013 & 2018), Rotokare Scenic Reserve (2017 & 2018) and Shakespear Open Sanctuary (2020) mark the first time hihi have been on the mainland of Aotearoa New Zealand since their extirpation in the 1880’s. These sites are managed as mammalian pest-reduced ‘mainland islands’, and differ from the island populations in that dispersal away from these protected areas is possible. Unfortunately, the Ark in the Park population has not persisted, all other populations continue to be supported with supplemental feeding and in most cases nest boxes. The populations are carefully monitored to track their population growth, most populations remain small but steady. To see details of our current management objectives and planned actions please see our management plan.